As a Marketing executive at PepsiCo, he lead them in the "Cola-wars"
in the 70-s and the 80-s. It was Sculley that came up with the famous blind
tests - The Pepsi Challenge - where people would choose their favorite Cola
after having tested unmarked mugs of the brown sugar waters. He also was
responsible for the Pepsi Generation campaigns, and when Pepsi Cola for the
first time became more popular than Coca Cola, much of the credit went to
Sculley.

Sculley was (according to himself) a major driving force
behind the perhaps most famous TV commercial ever, the Macintosh1984
commercial, inspired by the George Orwell book 1984. It has been aired only
once, during the 1984 Superbowl. It still stands out as a masterpiece and helped boosting Apple's sales, as well as the cult that still surrounds Apple.

After a power struggle that same year, he fired Steve Jobs from Apple. He
increased Apple's market share and oversaw the development of new computers
that could be used with other computer networks. But by 1993 the company was
suffering from a series of business failures - The NewtonPDA - and John Sculley was
replaced by Michael Spindler as the CEO. Shortly after, he left the company.

In October 1993 he became a chairperson and chief executive of Spectrum
Information Technologies, a wireless communications firm. Sculley left Spectrum
in February 1994 over a dispute with the company president. In 1995 Sculley
was appointed chief executive officer of Live Picture Inc., a graphics
software development company. That company went bankrupt in 1998, and now he has
a venture capital company together with two of his brothers .